System of electrical distribution



BEST AVAILABLE (3.9?

{No Model.) 2 Shasta-Sheet 1.

O. S. BRADLEY. SYSTEM OF ELECTRICAL DISTRIBUTION.

Patented Aug. 20, 1889.

ATTORNEYS BEST AVAILABLE COP.

4N0 Model.) 2 Sh'eets-Sheet 2. 0. s. BRADLEY. SYSTEM OF ELECTRICALDISTRIBUTION. No. 409,449. Patented Aug. 20, 1889;

WITNESSES: M INVE/VTOH 7 ram/Em".

' n'ewanrl useful Improvements e mtST/WAiLAB-L UNITED STATES PATENTOFFICE.

CHARLES SYSTEM ELECTRICAL' DISTR IBUTION.

SPECIFICATION forming part of Letters Potent No. 409,449,:lnted August20, race.

Application filed October 5, 1888; Bariil NOw287 82 (Ho modal.)

To all whom it may concern:

Ileit known that I, CHARLES S. BRADLEY,

a citizen of the United States, residing at Yonkers, in the county of\Vestchester and State of New York, have invented certain in Systems ofElectrical Distribution; andl do hereby declare the following to be afull, clear, and exact description of the invent-ion, such as willenable others skilled in the art to which it 81)- pertains to make andusethe some.

4 larly intended for the This invention relates to a new system ofelectrical distribution by alternating currents, and while adapted foruse in connection with electric-lighting appliances it isn'ioreparticutransmission of power over the ordinary alternating-currentcircuits, which under my system will be branch ed to supply motors oithe nltcrmiting-current type. In Letters Patent No. 390,439, issued tome October 2, 1888, I ha shown and described an electric motor of a t pwhich may be described a differential-phase motor, which is fed-by twoalternating cnrren ts, one of which is substantially a quarter-phasebehind the other in its time period, and it is'to such general type ofmotor that the present invention is more especially applicable.

My invention consists in asystem comprising an altemating-currentgenerator, a'pair 0f mains extending quarter-phase electric motors, eachhaving two supply-circuits, one circuit being direct from the mains andthe other circuit passing through an electroinotive device adapted toreceive the line-current and change its phase so that the currentseventually reaching the motor will be a quarter-phase apart, althoughbut a single generator is used and a single pair of mains.

'lho invent-ion further comprises a, means of regulating such a motor;and it consists also in the combination and arrangement of devices, 'allsubstantially as hereinafter fully described and claimed.

In the drawings which form part of this specification, Figure 1 is ndiagram illustratmg one of the simplest forms of my system, and Fig. 2illustrates the means of regulating the quarter-phase motor. Fig. 1-2 isan end the arrangement of its circuits.

"ing pnirs v v nectcd to diametrical points of the commutat-herefroni,one or more whether open or closed,"

A represents the generator of alternating.

currents, and l 2 are the distribut-ingnmins extending therefrom inilll) (l0$ll'0d'(illGClLlOll.

13 represents the armntnre of what I term the local-phase changer, andin' the figure the armature l; is a simple drunnm'nuiturc'witlirectitying-commutator c, on which bear the brushes d d, and thesc'arerespectively con: nccted to the terminals of the field-magnets c. On theshaft of armature 13, but insulated fronrt-he same and from each other,a're'four contact-rings f g h i, and of these the adjoinf g and h i arerespectively contor c, and therefore are connected into thearmature-circui tthat' is to say, rings h c are connected,respectively,to two opposite points, and rings f are respectivelyconnected to two other opposite points which stand at right angles tothe former.

'As described'in my previous patent, No. 390,439, it is obvious that thealternating current taken from the mains l 2 into the rings h i willpass into the armatureli and set the same in rotation, partof thecurrentbeing rectified by the commutator 0, so as to maintain a strongfield. The current then passes out through the rings f g, and on the wayhas its time period or phase altered-that is to say. it has beenretarded one-fonrth of it wave length.

Atit pointconveniently located in proximity to the describedphase-changing apparatus I place the electric motor M, and its arnmturcB is similar to armature ll, with the exception that it has norcctifying-commutator; but; it is provided with rings kl m n, which areconnected into the armature circuit of the armature 13 in exactly thesame manner as the rings f g]: i are connected into the circuit ofarmature B,:ind obvious y, if we can supply the moior-nrnmi-urc l withtwo currents difl'cring by a quarter-phase in their lime-period, themotor will operate successlully and with facility. From the branchsupplying cu rent from the mains 1 2 to the rings 11 iof the armature B,or fromlhc mains l :2 directly, I take the branch 3 -i and lead it tothe rings in. n of the nrumturc 1?, so that the currents supplied to thesaid rings m nis that circulating on the nminsl 2. From theconmct-ringsf g, I curry a pair of leads 5 0' l as the motor, but

be all uniform, an

3o their power or speed, or

tor-phase behind that 0 ively marked duced in them a so tially equaltoth adj ustmcnt is dcsirabl show BESTAVNLAB to the rings ir and as thecurrent which has passed ihr ugh armature]; has had its chase-.rrinriied-bne-qunrlcr oi a period it is obviots that the motor-armnturcB will be thereafter eontinuouslysuppliecl with twocurrents, one ofwhich will be onc fourth phase behind the other in time period. Y Anynumber of such motors and phasechanging devices can he connected to themain circuit 1 2, and at the same time a portion of the current lowingthrough themnins can i)0- used for electric lighting orany other desiredpurpose; I have shown the phasechahging device as substantially the samethis merely for the purpose of making clear its functions. In practice,however, since the armature B has no worlc to do except overeom e itsown to use at any particular point, and therefore the phase-changingdevices used throughout asystom of distribution of this character may dbeing very small can be set to work in out-of-the-way places, where theywill notbc interfered with.

In many cases where electric motors are used it is very desirable to beable to control both. I have devised means of doing, this in connectionwith the above system and have illustrated it graphically in. Fig. 2. Inthis figure the-two cir-' cults 5 6 and 3 4 onc carrying a currentsquarcarried by the ethereare respectively connected to the primary coils7 and 8 of the converters or transformers T T. Each of those convertersis in addition provided with three secondary coils, respect- 2') q r andp (1 T The coils pp are exactly alike and are made with onl 'a fewturns, 'in order to have induced in them aver-y lowelectro-motive force.The coilsqq are given afcw more turns, so as to have insomewhat higherelectromot-ive force than that induced in the coils pp". The coils r 'r''are won n d with moreturns still, so as to have induced in themcurrents whose eiectro-motive force will he substanat flowing in the.branches 3 i and 5 G.

I have herein described the transformers T T as heingprovided with threesecondaries; but I wish to state that if a wider range of c the numberof secondaries can be increased to'any required extent, and thedifference between them may be according to circumstances of use. Iar-ange these secondaries in connection with aswiteh- 6o in; device insuch manner that loan connect the terminals of an y two correspondingsecondary'coils into the rings him it of the motor-armature ii Thisswitch may be of any desired construction capable of doing the work;butI a particular form arranged-co do the double switching of each pairof coils simultaneously. This switch consists of s pivoted LE COP bar P,arrying metallic contact-arms r w, and in the path of the arms ln-rrangc.the respecttive contacts 9 10 ll and .12 '13 14. The ring 7; of themotor-armature is directly connectedto the corresponding terminal ofeach is likewise directly connected to the corresponding terminals of (11". The remaining terminals of the coils p q r are respectively carriedout to the contacts 9 1O 11 of the switch, and the similar remainingterminals of the, coils 11 g 1* of the transformer 'l are carried out tothe switch-contacts" 12 '13 14. The remaining rings Z and n are joinedby flexible connections to the contacts 2: and w of the switch-arm P.Thus arranged each of the transformers '1 T operatesindependently of theother. So far there will be no conflict, owing to the fact that thecurrents in the circuit 5 6' are one quarter-phase behind the currentsin the en'- cuit 3 4. Supposing, now, the motor-armature 13 1s at restand the switch-bar P is not resting upon any of the eontacts'none of thesecondary circuits of either of the transformers is closed, andconsequently no work will be done under these conditions. It, now, wewant to start the ,motor, with the points 9 and 12 of the switch.- Thisat once closes the circuit of secondary coil 1; into the armature Bthrough the com tact-rings is Z, and at the -same instant it likeintothe armature B through the contactrings m 12-, since in thetransformation which takes place, if any retardation of phase occurs inthe secondary currents, the secondary coils in both transformers will beaffected in the same degree and will have the same-time relation to eachother as the currents in the primary co'ils,and it follows from theforegoing that the armature B will now be supplied by ditions ofdifference of time-period in the supply-circuit of the motor, andconsequently the latter will be operated desired to give the motorforce, I swing the switch-bar P onto the contacts 10 and 13, and now thecoils q q receive the inductive effect and supply the resultingeleotro-motive force to the armature B. .Shouid'it be desired to providethe armsture with an. electro-motive force still higher, I swing the bar1 onto the contacts ll and 14, and now the inductive effect is producedthrough the secondary coils r 1. 3' suitable construction of thesecondary coil; of the transformers '1 T, I can supply the motorarmatureB with any 'electrounotiim force which may he desired, whether the namebe below or above thatpf the primary circuits, and thus I can effect anycondition of current which may he required in any particular case.

I claim as my invention- Ii. In a sysiem of electrical distriin'ition,the

the secondary coils p wise closes the circuit of the'secondary coil 2""the converted currents under the same con'' of the secondary coils p qr, and the ring m.

I swing the arm I ihio contact.

IOC

as before. If it is more electro-motive.

BEST AVAiLABLE COP combination of a generator of alt-crnat-ing currents,a pair of mains connected thereto, one or more multiple-circuitdifliereutiabphae electric motors having one circuit connected directlyto said mains and the other circuit or circuits connected to said mainsthrough an interposed elcctro-motive phase-changing de; vice adapted tochange the timeperiod of the currents passing through it.

2. In a system of electrical distribution, the combination of agenerator of alternati g on rrcuts, a pair of mains connected there 0,one or more double-circuit quarter-phase electric 'motors having onecircuit connected-directly to saidmains and the othercircuit connectedto the said mains'through an interposed electro-motive. device adaptedto change currents passing through it at one-quarter of a phase or wavelength.

3. The combination, with a quarter-phase double-circuit electric motor,of two trans-- secondaries in matched pairs into the motor circuits,substantially as described.

' 4. The combinati0n,'with an alternating current double-circuitelectric motor, of one or more transformers having primary coilsconnected to supply-circuits, and two or more graduated secondary coilsadapted to be connected to the inotor-circuits,'aml meenefor connectingsaid secondary coils into the motor-circuits as required, substantiallyas .described.

5. The combination, with a multiple-circuit alternating-currentelcctricmotor, of two or more supply-circuits having their cnrrcnteotrespectively differing phase, two or more primary or inducing coilsrepectively included in the snpply-circuits, two or more graduated setsof secondary coils in inductive relation to said primary coils, anda.-switch adaptedto connect the respective motor-circuits to any pair ofsaid secondary coils.-

In testimony whereof I affix my signature in presence of two witnesses.

' CHARLES s. BRADLEY.

Witnesses i T. J; Mc'lrenn, AnmoxrHomae.

